t's a case that has drawn comparisons to George Zimmerman's: A man is on trial for killing unarmed black teenager in Florida, claiming self-defense. But the case of Michael Dunn, which the jury is now deliberating, is only similar to Zimmerman's on a superficial level, experts say.

"When the details are broken down, there are significant differences, which make this much more of an uphill case for the defense," said Kendall Coffey, former U.S. Attorney and an NBC legal analyst.